There is known an in-vehicle control device provided with an information acquisition section that acquires information from a roadside device, and a control execution section that executes assist control based on the information acquired in the information acquisition section (refer to Patent Literature 1, for example).
The in-vehicle control device of Patent Document 1 receives information concerning a light color of an intersection signal from the roadside device. When the light color of the intersection signal in accordance with the received information indicates “prohibit entry” at the point when a subject vehicle enters the intersection, issuance of a warning is executed as assist control.